This invention relates to a molded, resilient self-cleaning piece of rubber and more particularly to a new and improved molded rubber sole which has a novel action of trapping air to clean itself when used in the environment of mud.
It has been known to construct shoe soles and heels of resilient deformable materials such as rubber, flexible plastics and other suitable compositions which have a plurality of transversely arranged corrugated ribs, undulations which project downwardly from and formed integrally with an upper section that is secured to the base portion of a shoe. The ribs generally project rearwardly from the front or toe section of the shoe towards the rear or heel portion and are inclined downwardly when viewed in side elevation on a shoe. Such ribs in shoe construction have been confined to the general use of facilitating the walking action or to ease the wearer's comfort in standing. The variations in construction of such deformable ribs has been claimed to increase resiliency and the forward gliding action imparted to the wearer's feet during walking or running.
The sole construction of the present invention which is particularly adaptable to overshoes is a completely new concept over such corrugated ribs by providing a plurality of transversely extending flexible fins that are thinner in construction and even in spacing and of such length that they trap air between adjacent fins upon deflection such that they spring back into original shape and will clean themselves if such fins come in contact with mud. One form of the invention is to have a plurality of fins disposed at approximately 45.degree. angle with respect to the horizontal plane and with the spaces between the fins being of a width that is equal to the width or thickness of the fins, and the height of the fins being equal to the depth of the space that is defined by pairs of adjacent fins. The fins are flexible such that the normal walking action of the overshoe will compress the fins in the sole to effect a trapping action of the air to clean the mud that is encountered on the lower most surface. The construction of the ground contacting element of a shoe or boot may be such as to have the angular disposition of the heel and toe portions at different angles relative to each other.